应用热水再循环技术实现宽负荷脱硝

Application of Hot Water Recirculation Technology to Realize Wide Load De-NO_x

燃煤电站锅炉在较低负荷运行时,脱硝设备(SCR)入口烟气温度可能低于脱硝催化剂正常工作温度窗口(通常为300℃~420℃),需要进行相关改造来满足电站锅炉低负荷投运脱硝设备的要求。通过对分级省煤器、省煤器烟气旁路、省煤器水旁路、热水再循环等几种目前常见的提高低负荷脱硝入口烟气温度改造方法的原理及特点进行了介绍,并详细介绍了热水再循环改造的技术路线,旨在为需要进行相关改造电厂的方案选择提供参考。

When coal-fired power units operate at low load,Selective Catalytic Reduction（SCR）inlet flue gas temperature have the possibility of lower than the De-NOxcatalyst temperature window（usually 300 ℃to 420 ℃）.Some renovation projects are needed to achieve low load DeNOxequipment requirements.This paper introduces some solutions,including economizer classification,economizer gas bypass,economizer water bypass,hot water recirculation,and analyses the principle and characteristic of these solution.And introduced hot water recirculation in detail.